Die heel assembly and method of utilizing



3, 1966 G. D. ROBB 3,268,273

DIE HEEL ASSEMBLY AND METHOD OF UTILIZING Filed Oct. 8, 1963 2 Sheets-Sheet 1 46 Wffik I 2W INVENTOR.

GEORGE D. ROBB I BY la 6 ATTORNEY Aug. 23, 1966 G. D. ROBB 3,268,273

DIE HEEL ASSEMBLY AND METHOD OF UTILIZING Filed Oct. 8, 1963 2 Sheets-Sheet 2 \K up UH! g\ 20 IKFHIIM/ in I L INVENTOR.

GEORGE D. ROBB.

ATTORNEY United States Patent 3,268,273 DIE IEEL ASSEMBLY AND METHOD OF UTlLIZlNG George D. Robb, Southfield, Mich., assignor to Federal Engineering Company, Detroit, Mich., a corporation of Michigan Filed Oct. 8, 1963, Ser. No. 314,792 2 Claims. (Cl. 308-3) This invention relates to an assembly of parts which may be attached to the two sides of a die set in order to act as a heel to absorb lateral forces which may be generated as the die halves are brought together in a pressing action. The invention additionally relates of a method of assembling and attaching such heel assemblies to a die set.

It is common practice in making dies for operating upon sheet metal to provide members which extend from each of the die halves in the direction of the opposite die half and carry wear plates with surfaces which extend parallel to the die motion and interact [with one another during a die forming operation to provide lateral stability to the die halves. In this manner these heels act to absorb the lateral forces which are generated in all but the simplest sheet metal dies during closure and to thereby prevent the lateral movement of the die or the punch. These heels are normally formed integrally with the die shoe and punch holder, requiring that these parts be formed from large blocks of steel or iron. Extensive machining is required to lower the surface of the shoe and the punch holder so that in each case the heel extends above the surface. After a punch holder and die shoe with heels are formed, the wear plates must be carefully fitted to the opposing heels to procure the desired slip fit between the wear plates supported on opposed heels when the die is closed. The wear plates must be aligned both laterally and angularly to insure a proper mating.

The present invention has as its primary object to provide a heel assembly which may be formed independently of the die shoe and punch holder on production equipment so as to obtain a perfect fit between a pair of heels by well known production techniques which may then be fitted to an otherwise finished die set in a simple and secure method. By providing die heels which may be securely attached to die and punch shoes rather than be formed integrally therewith a substantial amount of steel or iron and machining time is saved since the surface of the shoes does not have to be recessed below the level of the heels. Additionally the possibility of overcutting the integrally formed heels and thereby ruining an entire shoe or holder is eliminated.

In a preferred embodiment of the invention, the heel assembly comprises a male member and a female memher. The male member has a rectangular block formed with a cylindrical plug at one end and a flange separating the plug from the block. The female member includes a base having a pair of walls projecting therefrom and joining one another at 90 degrees so that their adjoining interior walls approximate the outer dimensions of the wear plates attached to the male block. A cylindrical plug is also joined to the female base. The latter includes a flange extending about its periphery. A guide pin is supported in a central hole in the male block and extends up beyond the block. This guide pin fits Within a bushing set centrally within the female member.

The heel assembly is so constructed that its parts may be attached to the die shoe and punch holder without creating any difficult problems of alignment. After the die shoe and punch holder are formed, they are clamped together and jointly bored. The male and female elements of the heel assembly are simply joined to the shoe and holder by press-fitting the cylindrical plugs into the bores in the die shoe and the holder. The latter members then are assembled together, the heel elements radially aligned with respect to one another and the two flanges bolted to the shoe and holder.

The heels may be mounted to the shoe and holder in any of a variety of arrangements to provide for the varying thrusts imposed by the dies. Since the assemblies are operative to accept thrust in two directions which are perpendicular to one another, the assembly is generally mounted with the two thrust-receiving surfaces facing inwardly toward the punch and die members.

It is therefore a further object of the present invention to provide a method of assembling and attaching heel assemblies of this type to a die set.

Another object is to provide a die heel assembly of this type which is economical to manufacture and assemble and is adaptable for use with a wide variety of die sizes and configurations.

Other objects and advantages of the present invention will be more readily apparent from the following detailed description of a prefered embodiment of the invention. The description makes reference to the drawings in which:

FIGURE 1 is a perspective view of a die set incorporating the present invention with parts broken away;

FIGURE 2 is a sectional detail view of one of the heel assemblies shown in FIGURE 1;

FIGURE 3 is a sectional view taken along the lines 3-3 in FIGURE 2;

FIGURE 4 is a sectional view taken along the lines 4--4 in FIGURE 3;

FIGURE 5 is a first schematic view showing an arrangement of the wear plates and the direction of the lateral support provided by the plates;

FIGURE 6 is a second schematic view showing a second arrangement of wear plates and the direction of lateral support provided; and

FIGURE 7 is a third schematic view showing a third arrangement of Wear plates and the directions of the lateral support provided.

Referring to the drawings in detail, FIGURE 1 shows a die set comprising dies halves including a lower die 10 fixed upon a die shoe 12 which in turn rests upon a base 14. A punch 16 is disposed opposite to and immediately above the die 10. The punch is fixed to an upper punch holder 18. The die shoe and punch holder extend horizontally beyond the ends of the die and punch members 10 and 16.

A heel assembly, indicated generally at 20', is located at opposite corners of the die set. The heel assembly consists of an upper female member 22 and an opposing lower male member 24. The male member includes a rectangular block 26 having a cylindrical flange 28 and a lower cylindrical plug portion 30. A hole 32 extending through the central portion of the block 26 includes a narrow lower portion 34. An elongated L-shaped wear plate 36 extends horizontally along a recess 37 in the block 26 and is fixed to the block. The male member 24 is normally fixed to the die shoe 12 by means of bolts 38 which extend through matching holes in the flange 28 and the die shoe.

The upper female member 22 consists of a flat base portion 40 having a flange 42 extending along its periphery. A cylindrical plug 44 projects upwardly from the base portion 4t) and a pair of walls 46 project downwardly from the base portion in an L-shaped configuration matching the outer dimensions of the wear plate 36. The female member 22 is normally fixed to the punch holder 18 by means of bolts 48 which extend through matching holes in the flange 42 and the punch holder 18. A bushing 50 fits within a vertical central opening 52 in the base 40 and plug 44, located directly above the central opening 32 in the block 26.

The die shoe 12 is provided with a vertical bore 54 directly below the male member 24; the plug 30' is normally press-fitted Within the bore. Similarly, the punch holder 18 includes a vertical bore 56 into which the plug '44 is normally press-fitted.

A guide pin 58 is adapted to fit vertically within the matching central openings 32 and 52. The guide pin includes a narrow lower portion 60 which rests within the lower portion 34 of the central opening 32, a central portion 62 resting in the upper part of the opening 32, and an upper portion 64 fitting within the bushing 50. When the female member 22 is disposed above the male member 24 with the guide pin 58 engaging their respective openings, the walls 46 contact the outer surfaces of the wear plate 36. This abutment provides the lateral support necessary to prevent lateral movement of the die or punch 16 during the punching operation. As the punch 16 is moved between its open and closed position with respect to the die 10, the punch holder 18 and the attached female member 22 are correspondingly translated vertically along the upper portion 64 of the guide pin 58.

The required orientation of the heel assembly within the die set and the number of heel assemblies necessary to provide sufiicient lateral support is dependent upon the type of punching or forming operation being employed. FIGURES 5-7 illustrate three exemplary orientations for the heel assemblies, each providing lateral support in difierent directions.

In FIGURE 5, the heel assemblies are oriented to provide lateral support in the directions indicated. This orientation would be useful when the principal thrust forces exerted by the die and punch are in the diagonal direction and are directed toward the corners of the die set occupied by the heel assemblies. The orientation shown in FIGURE 6 will resist forces which are parallel to the edges of the die set. The arrangement of FIGURE 7 will resist forces which originate from a large area at the center of the die set and are principally directed toward the heel assemblies shown.

It can thus be seen that the heel assemblies may be oriented in any desired configuration so as to resist lateral forces of various magnitudes extending in any direction in the die set.

Heel assemblies of the type described above may be assembled and attached to a die set without creating any significant problems of alignment. The die shoe and punch holder are first clamped together and jointly bored to produce the upper and lower bores designated at 54 and 56. The male member 24 is joined to the die shoe 12 by press-fitting the plug in the lower bore 54. The female member 22 is similarly joined to the punch holder 18 by press-fitting the plug 44 in the upper bore 56. The guide pin 58 is placed in the central opening 32 in the block 26 and the punch holder 18 and female member 24 set in place on the upper portion 64 of the guide pin. The male and female members are then radially aligned by rotating them about the guide pin until the walls 46 and the Wear plates 36 abut each other and are in the desired orientation for resisting the lateral forces created during the punching operation. The flanges 28 and 42 and the adjacent die shoe and punch holder are then drilled, tapped and bolted together.

The resulting assembly is in perfect alignment and capable of withstanding the lateral forces created during the punching and forming operation. The heel assembly may be easily removed from the die set simply by pulling the female member 22 offthe guide pin 58 and removing the bolts from the flanges. The male and female members may then be knocked out of their press-fitting in the bores 54 (and 56.

While the arrangement described above employs a guide pin for alignment purposes, the shape of the dies may be such as to eliminate the need for the guide pin. In such case the matching central openings 32 and 52 of the bush ing 50 may 'be eliminated. Dowels and 72 are then placed in openings 74 and 7 6 extending respectively through the flanges 28 and 42, and the die shoe 12 and punch holder 18. These dowels then permit the axial alignment of the male and female members.

Having thus described my invention, I claim: 1. A heel assembly for attachment to the die shoe and punch holder of a die set, comprising:

a male member removably attached to one of said two members of said die set, said male member having a central opening;

L-shaped Wear plates attached to said male member;

a female member removably attached to the other of said two members of said die set and having a central opening in axial alignment with said opening in said male member, said fem-ale member having L- shaped walls corresponding to said Wear plates an adapted to abut thereagainst;

and a guide pin fitted within said first and second central openings.

2. A heel assembly for attachment to the die shoe and punch holder of a die set, comprising:

a male member having a block, a flange portion bolted to said die shoe, a central opening in said block, and a plug press-fitted in a corresponding opening in said die shoe;

L-shaped wear plates attached to said male member;

a female member having a base, a flange portion bolted to said punch holder, a central opening in said base in axial alignment with said opening in said block, L-shaped Walls corresponding to said wear plates and abutting thereagainst, and a plug press-fitted in a corresponding opening in said punch holder;

. and a guide pin fitted within said first and second central openings.

References Cited by the Examiner UNITED STATES PATENTS 1,474,862 11/1923 Tolbert 22-110 2,180,282 11/1939 Leighton" 2,288,136 6/ 1942 Janizewski 308--5 2,627,313 2/ 1953 Marsiliue 308-4 3,039,157 6/1962 Bobenmyer 22-110 X 3,039,829 6/ 1962 Onu-lak 308-4 3,176,378 4/ 1965 Janizewski.

DAVID J. WILLIAMOWSKY, Primary Examiner. DON A. WAITE, Examiner.

L. L. JOHNSON, Assistant Examiner. 

2. A HEEL ASSEMBLY FOR ATTACHMENT TO THE DIE SHOE AND PUNCH HOLDER OF A DIE SET, COMPRISING: A MALE MEMBER HAVING A BLOCK, A FLANGE PORTION BOLTED TO SAID DIE SHOE, A CENTRAL OPENING IN SAID BLOCK, AND A PLUG PRESS-FITTED IN A CORRESPONDING OPENING IN SAID DIE SHOE; L-SHAPED WEAR PLATES ATTACHED TO SAID MALE MEMBER; A FEMALE MEMBER HAVING A BASE, A FLANGE PORTION BOLTED TO SAID PUNCH HOLDER, A CENTRAL OPENING IN SAID BASE IN AXIAL ALIGNMENT WITH SAID OPENING IN SAID BLOCK, L-SHAPED WALLS CORRESPONDING TO SAID WEAR PLATES AND ABUTTING THEREAGAINST, AND A PLUG PRESS-FITTED IN A CORRESPONDING OPENING IN SAID PUNCH HOLDER; AND A GUIDE PIN FITTED WITHIN SAID FIRST AND SECOND CENTRAL OPENINGS. 